Chemical and biological studies will continue on slaframine (SF) biogenesis in Rhizoctonia leguminicola, and will particularly focus on the derivationization of position 6 and how the 5-membered ring of SF is formed. 5,5-d2 pipecolate and R-3H-pipecolate will be fed to the fungus; SF formation is blocked by NH2OH in resting cells which may indicate transamination of 4 via a B6 requiring enzyme. 4 may accumulate under these conditions such that is might be studied in fungal extracts as a substrate for amination and reduction. Conditions will be sought in cell free systems such that intermediates of Scheme 1 may accumulate from pipecolate and malonate. If successful appropriately deuterated precursors will be synthesized and intermediates formed biologically analyzed via mass spectrometry to give clues about the mechanism of the initial condensation. This project contained formulas, drawings, tables or nonkeyable data which are not shown above.